Conventional rowing machine used for gymnastic purpose always includes a seat movably rolling on a seat base when operating the two oar handles to imitate the rowing of a boat, which however has the following defects:
1. The machine is constructed as a fixed type to be lacking of vividness so that its rowing operation just serves as a physical training without having the interested feeling as felt in a true boat-bowing.
2. The rowing action is operated by merely moving the seat reciprocatively along the rails under the seat in a regular way, to thereby be impossible to feel or enjoy the waving as a true boat floating on a tide or water waves.
The present invention has found the defects of a conventional rowing machine and invented the present dynamic rowing machine.